I am having the same issue.  I tried to send several to see if it might be an issue with a particular file but that does not seem to be the case.

This is a major issue with me as well.  Just began this week. We can't send e-organizers with customized letters.  Is Lacerte working to correct this?

Support is telling me that maybe the last update is not playing nice with my customized engagement letter.  Really?

Support identified the issue as the bitmap of my signature.  Other bitmaps, like my letterhead, worked fine. For me it was not an issue removing it so that is what I did and all went well.  Would have tried to recreate the bitmap but was not worth the effort. I use the same bitmap signature file for pdf versions of organizer and all works fine.

@swack Thank you for posting your solution. I hope it helps @GITAX and @jerry

Thank you, helped me!